Concrete Sludge Powder for Soil Stabilization

Abstract

Concrete sludge is an industrial waste produced from ready-mixed concrete plants. Every year, a large quantity of concrete sludge is produced in Japan. At the same time, practical, large-scale disposal options for the concrete sludge are limited, and the cost of disposal is high. Furthermore, the disposed concrete sludge may cause serious environmental and land use problems. A new way to recycle the concrete sludge and reuse large amounts of it is much desired. An innovative technology to cost-effectively recycle concrete sludge and use the recycled material in road construction was developed. Experiments were conducted to study the suitability and effectiveness of the dried sludge powder as a soil stabilizer to improve the load-bearing strength for a clay soil with high moisture content. The tests results showed that adding dried sludge powder to the selected soil with high moisture content can significantly decrease the water content, plasticity index, and frozen heave of the soil while greatly improving the load-bearing strength. The stabilizing effectiveness of the dried sludge powder is greater than that of quicklime in early stages. However, to obtain the best benefit and the best construction quality, some measures should be taken.